Drawing instrument



March 1s, 1936;(

B. M. sHAuB 1,751,366

DRAWING INSTRUMENT Filed Sept. 13, 1926 2 vSheets-SINN'- l Illl March 18, 1930. B. M. sHAUB 1,751,366

DRAWING INSTRUMENT l n Filed Sept'. 13. 1926 2 Sheets-Sheet 2 Patented Mar. 'i 18, 1930 BENJAMIN M. SHAUB, OF ITHACA, NEW YORK DRAWING INSTRUMENT Application filed September 13, 1926. Serial No. 135,126.

This invention relates to certain improvements in drawing instruments; andthe nature and objects of the invention will be readily recognized and 'understood by those skilled in the arts involved inthe light of angles to each other, so as to provide guide edges'along which lines can be drawn on a surface upon which the instrument is laid and maintained in the desired position. Generally these straight edge types of instrument are employed in mechanical or simi* lar character of drawing in which the lines are laid'off or drawn accurately to scale, scale markings being provided on the instrument, and experience has established the fact that considerable inaccuracies result ina drawing due to the errors arising from the thickness of the pencil point or variations in the iineness thereof in drawing a line by guiding the pencil point along and against an edge of the instrument.

The present invention has as one of the main objects the reduction to a negligible degree` of the foregoing inherent difiiculty with the straight edge type of drawing instrument, by so designing the edges thereof and arranging the scale markings on the instrument with respect to the guide edges, as to compensate forthe pencil point thickness or iineness Variations and permit of drawing therewith without material error or inaccuracy.

A universally employed and necessary form of the above mentioned straight edge type of drawing instrument is the well known triangle in the form of a fla-t triangular plate having the edges thereof at the desired angles to each other;l and a further characteristic of the invention resides in the design and arrangement of a series of scale markings on a triangle, in such a relation with respect to the edges thereof, that the instrument can be eiliciently employed for accurately locating vertical, horizontal, or inclined lines on a. drawing through the medium of the instrument edges and the scale markings.

A further obj ect of the invention is to provide a'drawing instrument of the straightedge type in the form of a triangle having truncated ends which in cooperation with scalesmarked on the instrument, enable its use toaccurately locatev and draw horizontal and Vertical lines in a drawing from a given line or point on the drawing, or the surface upon whichthe drawing is to be formed.

Another object of the invention is the provision of a drawing instrument of the straight edge type formed with auxiliary guide or ruling edges disposed in a certain 7 relation to the main` guidey or ruling edges of the instrument, for the purpose of drawing guide lines for letteringa drawing, or for locating lines' thereon.

A further ob'ect of the vinvention is Ato provide for locating and drawing section lines on cross section areas of a drawing with a drawing instrument of the straightedge type in an accurate and uniformly spaced manner, by forming section line scale markings on the instrument in such a relation to the guide or ruling edges thereof as to enable the use of the instrument to locate and uniformly space and draw the desired p section lining. v

A still further object of the invention is to provide a design, construction and arrangement of straight-edge type of drawing or drafting instrument which combines and presents in a single instrument the characteristics of a scale, a triangle. and a section liner and lettering guide, which instrument is. of simple form capable of efficient and accurate use for the several purposes mentioned, as well asv other purposes and uses which may arise in drawing work, and which is capab e of ready manufacture without special machinery, at a relatively low cost.

' Another characteristic of the invention resides in the provision of a straight-edge type of drawing instrument formed of transparent material having the scaleY markings formed on the under side and visible in proper position from and through the upper side of the instrument when placed in position on a drawing, and in the arrangement and relative location of the scale markings with respect to the guide or ruling edges of the instrumentso as to secure accurate results from their use and'minimum possibility of error in their reading in drawing and measuring a line therefrom.

With the foregoing general ob]ects, and certain other objects and results in view which will be readily apparent from the following explanation, the invention consists in certain novel features in construction and in combinations and arrangements of elements forming the invention, as will be more lfully and particularly referred to and specified hereinafter.

Referring to the accompanying drawings:

Fig. l is a top plan view of a drawing instrument of the invention in the form of a truncated triangle having the scale markings formed and arranged thereon in accordance with the principles of the invention.

Fig. 2, is a vertical transverse section through the instrument between the edges m and y, thereof, to show the beveled form of the edges w and y.

Fig. 3, is a view in end or edge elevation of the instrument showing the beveled formation of the guide edges.

Fig. 4, is a detail view, more or less diagrammatical. and showing the location of the zero or datum line of the scale with respect to the beveled guide edge, and showing the instrument in operative relation with a T-square, a portion only o f the T-square being shown in vertical section.

Fig. 5, is a view more or less diagrammatical showing the use of the instrument 'with a T-square for locating a vertical line to the right (or to the left) of a vertical center or base line of a drawing. i

Fig. 6, is a view more or less diagrammatical, showing a use of the instrument for locating a horizontal line above (or below) a horizontal base or center line of a drawing.

-Fig. 7, illustrates more or less diagrammatically, the use of the instrument of the invention to locate lines normal to a 45 line of a drawing.

Fig. 8, is a more or less diagrammatical y view showing the use of theinstrument to locate lines above and below a base or center line, particularly when the lines to be located angle embodying and incorporating the invention, is presented inthe accompanying drawing purely by way of example and not of limitation, for the purpose of illustrating Yand explaining the principles and various features of the invention, but it is to be understood, as will be clear from the following de-v scription, that the invention in all features is not restricted to the triangular form shown but is of general application to drafting or drawing instruments of the straight-edge and other types. While the triangle shown is of the 45 type, there is no limitation intended thereby, for obviously triangles of the 30-60 and other combinations of angles may be employed within the range and principles of the invention, as will be understood by those familiar with drawing instruments.

In Figs. 1 to 4, of the drawings a drawing instrument 10 of the straight-edge type in the form of a 45 triangle is shown constructed and arranged in accordance with the present invention. The triangle 10 is formed of a flat triangular plate of transparent material, such as celluloid or the other materials well known in the art and used for the purpose, and presenting the guiding or ruling straight edges T and Z along the legs of the triangle and the edge Y along the hypotenuse of the triangle. Following the principles of the invention the triangle 10 is truncated, that is the ends or apexes at the points of intersection of the hypotenuse edge Y with the leg edges T and Z, are cut off to form the straight edges A, as will be clear by reference to Fig. 1 of the drawings in particular. Along each leg of the triangle 10, a series of spaced, parallel scales S, are formed spaced inwardly from and parallel with the leg edges T and Z, and extending from the truncated ends A of the triangle to the opposite leg edges T and Z, respectively, with the scales S intersecting, as shown in Fig. l. The scales S are formed 1n any well known manner on the under side or surface 30 of the triangle l0 in such a manner and so arranged as to be visible and read from the upper side or surface 20 with triangle 10 laid in operative position upon, and surface 30 and scales S coincident with, the surface on which thewdrawing is to be prepared. The scales S are numbered and read from zero at' their opposite ends inwardly from the respective triangle edges adjacent thereto, and each scale S is preferably given lao a number, as shown by the numbers (4), (2)

(6), and (3) in Fig. 1, to indicate the number of inches, for example, on the scale to represent a standard foot, although obviously other measuring standards may be employed, such as the metric system. The parallel scales of or A, of the triangle 10, and this is accomopening through the body of the triangle,

plished in the present embodiment by forming the guiding edges with a downwardly and 1nwardly inclined beveled surface B, from a point below the upper surface 2O to and joining the lower surface 30 at F, as clearly shown' by Figs. 2, 3, and 4 of the accompanying drawings. The bevel B thus forms the edges of the triangle undercut withan upper ed e bearing surface G for abutting the edge of a T-square 40, or other instrument with which the triangle may be employed, yas shown by Fig. 4. According to this feature of the invention, the scales S* are arranged with their zero pointsl located 1n a vertical line or plane midway between the edges F and G of the edges of the triangle, resp'ectivelyY adjacent the opposite ends of the scales, as indicated by the zero or datum line or plane D in Fig. 4 of the drawings, 1n connection .with the scale end markings as shown in Fig. 1. When the triangle 10 is used as the straight edge to locate a line,- Vthe pencil point is -positioned by the bevel face to draw a line coincident with the Vzero or datum line of the scale. In using the T-square 40, the triangle 10 is employed to locate the T-square so that a line drawn along the edge of the square will'coincide with the zero on the triangle scale in that position.- In this manner, a line can be drawn to coincide with the zero of the scale whether the triangle or the T- square is used to guide the pencil in drawing a line. The bevel straight edges further function and operate to limit and restrict errors due to the variations of the pencil point fineness or thickness.

A series of scales S are formed in a similar manner to scales S, on the under surface of the triangle 10 from a central portion of the hypotenuse edge Y of the triangle 10, ex-

tending inwardly therefrom at right angles thereto, to a ruling or guiding edge X formed parallel with edge Y by an elongated slot or for a purpose appearing hereinafter. The ruling or guiding straight-edge X is formed with a bevel under face B, simllar to edge Y,

and the scales are arranged to read from zero at their opposite ends adjacent edges X and Y, respectively, with their zero or datum lines disposed in a vertical plane midway of the bevels B of edges X and Y, in a manner and for the purpose explained in connection with scales S and triangle edges A, T, and Z.

At opposite sides of the scales S, and between these scales andthe scales S at oppo site sides thereof, a line I is formed on the under surface 30 of triangle 10 and parallel to the'etriangle leg edge respectively adjacent thereto, that is one of the lines I parallel to edge T and the other thereof parallel to edge Z, as shown in Fig. 1 of the drawings. Intersectng and extending across. each line I,is an elongated slot or opening forming the straight edge H disposed at a predetermined angle or slope with respect thereto, in the present example at a 2: 1 slope with the line I, .and these sloping or inclined guide edges are employed for forming or drawing slope guide lines for lettering, in orderl to give the desired slope to lettering placed on a drawin j. frThe triangle 10 is further designed' for use in forming section liningy on a drawing, by

the provision adjacent to the edge of the triangle guide or ruling edges T, Y, and Z, on the under surface 30 of the triangle, and parallel therewith,of the parallel lines O, P, and Q, spaced different distances apart and from the triangle edge with which they are respectively adjacent and parallel. In the lpresent example the lines O, P, and Q, extend at one end from a verticalline and at their opposite ends terminate different distances from the commonvertical line, although not so limited, so as to be more readily distinguished in use, while a single line R 'parallel to the triangle edge extends in the opposite direction from lines O, P, and Q, and

vslightly closer to the adjacent triangle edge than the line O of each series. A set of the section lining guide lines O, P, Q, vand R,-

are formed along and parallel to each of the leg edges T and Z, respectively, of the triangle 10, while a-set of these lines O, P, Q, and R, are formed adjacent the hypotenuse edge Y at opposite sides of the series of scales S extending from this edge, as shown in Fig. 1 of the drawings, although not so limj lines J and K extending from one side of,

and the lines M and N extending from the opposite side, of a common vertical line,

while the line L is disposed beyond the outer end of line K but between this line and the h form of a triangle, constructed, and having the desired distance, and the line desired isl thescale and line arrangements thereon for cooperation therewith, as above described, referring now to Fig. 5 of the drawings, when it is desired to locate a line at a distance of, for example,one inch from a vertical base or center line U of a drawing, and to the right, the triangle is placed on the drawing with leg edge Z against edge C of a T-square 40 `and edge T verticallyy disposed and to the right of the base line U. Then by moving the triangle until the base line U is coincident with the one inch marlk of a scale S parallel to leg edge Z, reading from the Zero line at edge T, a line is drawn along leg edge T which is the line desired located at one inch to the right of and parallel with the base line. To locate the line to the left of base .line U, the triangle is turned with leg T against the T-square 40 and the scale S par.- allel to edge vT -used to locate the edge Z at then drawn along edge Z. In bothfcases', the errors due to variations in pencil point fineness are reduced or limited by the bevel structure of the triangle edges in the relation with the zero or datum lines of the scales` S, and the lines drawn caused to coincide therewith, as previously referred to.

When it is desired to locate and draw a line above a base or center line V disposed horizontally, the triangle 10 is placed lon the drawing with its edge T against the T-square 40, as shown by Fig. 6, and the T-square and triangle areitheii moved upwardly or downwardly until the base line V is coincident with the proper marking on scale S which is parallel to edge Z, that is a vertically disposed scale, so as to locate the truncated edge A ofthe triangle at the required distance above the base line V. A' line can then be drawn along edge A at the desired distance above the base line V, and if edge A is not of suflicient length, the line can be coinpleted by raising the T-squ'are to the line already drawn and continuing the saine by using T-square edge C, as will be readily understood. A line -can ,be located and drawn at a required distance below the horizontal base line V in a similar inanner. The lines so located and drawn are accurately placed due to the beveled edge construction and errors are reduced and limited in the resulting drawing. By the beveled edge of the triangle in the case of the' line below the base line, for example, the edge of the T-square causes a line drawn therealong to coincide with the zero of the s cale, and thus/accurately locates the drawn scale S between guide edge X and triangle edge Y, .by measuringalong scale S to locate edge Y at the desired point, a line can then be drawn along Y normal to the line A,

as indicated in Fig. 7 Similarly, if desired or found expedient, the ruling edge X can be used to locate andv draw lines normal to the line A. vIn the same manner lines can be located and drawn in the other uadrants by changing the position of the triangle 1() to locate the hypotenuse edge Y'in the desired quadrant, as will be clear from Fig. 7

Scales S and the guide or ruling edges X and Y can be employed to locate lines above and below a horizontal center or base line V, in a manner shown by Fig. 8 of the accompanying drawings. The triangle 10 is placed with edge Y abutting T-square 40, and is moved upwardly or Vdownwardly until the base line V is at the proper marking of scale S to'locate edge X at the desired distance from the base line. After locating edge X, a line' is then drawn therealong which will be at the desired location above baseline V. In the event that the line desired is longer than edge X, the T-square 40 can be employed to continue and complete the same, in the usual manner understood in the art. `A line can be located at a desired distance below base or center -line V, in a manner similar to that described above, by changingthe position of triangle 10, or by locating edge Y or the T- square at the required distance and then drawing the line. The vedge X and scale S are of particular utility and convenience when the lines to be located and drawn are near or in proximity'to the upper or lower edges of the paper or other surface on which the drawing is to be prepared.

The foregoing uses and applications of the triangle 1Q in the accurate.location of lines on a. drawing are merely illustrative of sonic of ,the purposes of the instrument of the invention, and it will be obvious that the instrument may be employed in a large variety of other ways for other purposes in the location and formation of lines. With triangles of other angle'combinations than that of the example shown, the uses will be varied, and as with triangle 10, these instruments of the invention can be operated to meet the different conditions encountered in the preparation of .various drawings and the accurate l0- cation and forming of the lines from the instrument scales vin association and cooperation with the error/compensating guiding or ruling edges.

The use of the lines J, K, L, M, and N for locating and vdrawing lettering guide lines is illustrated by Fig. 9 of the drawings. 'lhe lines M and N are employed for drawing guide lines for upper case letters in lettering a drawing, in the following manner. A line B is located on the drawing and drawn along the edge C of T-square 40. The triangle, in the present example, is placed with edge T against the T-square and is moved therewith until the line M is coincident with the drawn line B when another line C is drawn along.

the edge T of the triangle or edge C of the T-square located by the triangle edge T. The line C will then be properly spaced from guide line B', due to spacing of line M from triangle edge T. The triangle 10 and .T- square are then moved downwardly until line N is coincident with drawn line C', and a line D' is thenjdrawn along edge C of the triangle, giving the proper spacing between the lines of lettering. Line\ E', is then drawn by placing line M coincidentwith line D', in the same manner as line C was located and drawn. The above operations are repeated until the desired number of lettering 'guide' lilies are formed.

The series of lines J, K, and L, are employed for locating and drawing guide lmes for lower case lettering, and the operatlon is similar to that inusing lines M and N. A line F is drawn and then triangle line J is placed in coincidence with drawn line F', and4 line G' is located and drawn. Triangle line K is then placed coincident with drawn line G and line H' is located and drawn. To secure the proper spacing between lines of lower case lettering, triangle line L is placed coincident with drawn line H and the line I located and drawn, the lettering guide lines J and K then being located and drawn in a manner similar to that described with reference to lines G and H. v

Preferably, all of the lettering guide lines in the horizont-al position are` drawn along the edge of the T-square, and the bevel edge of the triangle properly locates the T-squa're edge for such lines.

After the lettering guide lines above described are located and drawn on the drawing, the slope guide lines for the letters can be located and drawn by means of line I and edge H of the triangle shown in Fig. l and described hereinbefore. The triangle is placed with a line I of the triangle coincident with a lower lettering guide line, such as line C or H' of Fig. 9, and a line drawn along edge H across the lettering guide lines which will be at the desired slope for the lettering. This is repeated along the letter-v ing guide lines at intervals to provide the lettering slope guide lines between which the letters'are formed. y

The triangle 10 through the medium of the series of parallel lines O, P, Q, and R, is capable of operation and use as a [section liner for, drawing cross section lines on section areas of a drawing, and this use is disclosed in Fig. 10 of the accompanying drawings. An area 50 of a drawing is diagrammatically indicated in Fig. 10, which is to'bc section lined. The triangle l0 is place-d with the edge Y across the lower left hand corner of area 50, with the edge T against T-square edge C, `and a line L' is drawn along edge Y across lthe area. The triangle is then moved to the right along the edge C of T-square 40 until triangle linev O, parallel with edge Y, is coincident with the line L', when another line L is drawn along edge Y. This operation is repeated,'coinciding triangle line O with the last drawn line L', until the area is covered. v A seriesof accurately spaced section lines L repeated over the cross section area, and the diiliculties in unmeasured section lining with unequal spacing between lines is eliminated, while the time required to section line an area is materially reduced. When a diii'erent spacing between the section lines is required, the triangle lilies P, or Q, are employed instead of line O. To secure section lining to indicate a particular material, such for example as steel, the lines O and R are used lalternately to produce thesection lines M shown in Fig. l0. The series of lsection line markings O, P, Q, and R on the triangle l0, parallel to the guide edges f T and Z at the legs of the triangle are employed in the same manner as explained in connection with the lines O, P, Q, and R,

parallel to the hypotenuse edge Y of triangle 10.

Thus, the invention provides in a single straight-edge type of drawing instrument, a triangle, section-liner, and lettering guide, as well as providing for the reduction and limitation of errors in laying olf and drawing lines of a drawing accurately to scale. The instrument is simple in construction and readily operated and used byl unskilled draftsmen, such l'as drafting students. The accuracy of a drawing and the speed at which it can be prepared are materially increased by the use of these instruments of the invention, and where of the triangle type, a series thereof of diierent angle combinations will increase andwiden the range of their usefulness in preparing various types and characters of drawings. With the invention, by fixing one line on the instrument coincident with a line on the drawing, that is, a center line, for example, the other lines can be accurately located therefrom in all cases, and by the bevel edge construction the varia-A tion in the location of lines due to variation in the thickness of a pencil point in use, is ref duced.

Attention is here directed to the fact that the term straight-edge is employed herein in a broad generic sense, as ruling or guiding edge of a drawing instrument, and is to be so I claims.

It is also evident that various changes, modifications, variations and substitutions might be resorted to without departing from the spirit and scope of my invention, and hence I do not wish to limit myself to the exact and speciiic disclosures hereof.

Desiring to protect my invention in the broadest manner legally possible, what I claim is: v

1. A drawing instrument embodyin a truncated trian le having its under ed es beveled, there being a scale parallel to an e ge of the triangle extending between two opposite edges, said scale having its zero line located in a verticalplane midway of the bevel at the respective adjacent ed e.

2. A drawing instrument em odying ar truncated triangle with a scale formed thereon normal to two parallel edges and numbered from zero at each edge, the said arallel edges undercut and the zero lines of t e scale located midway of said undercut, respectively.

3. A drawing) instrument embodying a' triangle, there ing a slot formed inthe triangle spaced inwardly from the hypotenuse edge thereof to provide a guide edge parallel with the hypotenuse, there also being a scaleformed on the triangle and extending between said slot. edge and the hypotenuse edge and transversely disposed with respect to such edges.

,4. A drawing- 'instrument embodyin a truncated triangle having the under edges thereof beveled inwardly, there being scales on the triangle parallel to the leg edges thereof, respectively, and extending between each truncated edge and the opposite leg edge respectively, said scales numbered from zero at each edge but with the zero line located in a vertical plane midway of the bevel of the adjacent edge, respectively.

5. A drawing instrument embodying a iiat plate member having at least two guide edges at right angles to each other, with a scale on the member parallel to one of said guide edges and extending at v one end i to the adjacent guide edge, the adjacent guide edge undercut and the zero line of the scale located in a plane normal to the plate and substantially midway of the undercut of said adjacent edge.

6. A drawing instrument embodying a transparent `member having an undercut guide edge, the said member having aseries of lines formed on the under surface thereof parallel to said guide edge and spaced inwardly predetermined distances from a plane August, 1926.

normal to the member and midway of the undercut edge, respectively, for locating said guide ed e 1n, forming a series of spaced parallel lmes on a drawing.

BENJAMIN M. SHAUB. 

